/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
    * with the License.  You may obtain a copy of the License at
    *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  package javax.faces.component;
  
  import java.io.Serializable;
  import java.util.AbstractList;
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * @author Manfred Geiler (latest modification by $Author: skitching $)
   * @version $Revision: 676298 $ $Date: 2008-07-13 05:31:48 -0500 (Sun, 13 Jul 2008) $
   */
  class _ComponentChildrenList
          extends AbstractList
          implements Serializable
  {
      private static final long serialVersionUID = -6775078929331154224L;
      private UIComponent _component;
      private List<Object> _list = new ArrayList<Object>();
  
      _ComponentChildrenList(UIComponent component)
      {
          _component = component;
      }
  
      public Object get(int index)
      {
          return _list.get(index);
      }
  
      public int size()
      {
          return _list.size();
      }
  
      public Object set(int index, Object value)
      {
          checkValue(value);
          setNewParent((UIComponent)value);
          UIComponent child = (UIComponent) _list.set(index, value);
          if (child != null) child.setParent(null);
          return child;
      }
  
      public boolean add(Object value)
      {
          checkValue(value);
          setNewParent((UIComponent)value);
          return _list.add(value);
      }
  
      public void add(int index, Object value)
      {
          checkValue(value);
          setNewParent((UIComponent)value);
          _list.add(index, value);
      }
  
      public Object remove(int index)
      {
          UIComponent child = (UIComponent) _list.remove(index);
          if (child != null) child.setParent(null);
          return child;
      }
  
  
      private void setNewParent(UIComponent child)
      {
          UIComponent oldParent = child.getParent();
          if (oldParent != null)
          {
              oldParent.getChildren().remove(child);
          }
          child.setParent(_component);
      }
  
      private void checkValue(Object value)
      {
          if (value == null) throw new NullPointerException("value");
          if (!(value instanceof UIComponent)) throw new ClassCastException("value is not a UIComponent");
      }
  
 }